P06D4Sensor Reference Voltage E Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The engine module feeds sensors from several regulated 5 V reference circuits; a short at one sensor pulls the whole circuit down and all its sensors report at once – unplug them one by one to find the culprit. P06D4 means reference E is too high – often a sensor signal wire shorted to 12 V. No manufacturer document available to us names P06D4 itself; Ram's 6.7 L Cummins uses the neighbouring P06D3, and GM reports circuit E under P06D2. Sensors on the circuit then read too high.
- What you may notice
- Check engine light
- Several sensor codes at once
- Reduced power or limp mode
- Possibly starting problems
- Likely causes
- LikelyReference or sensor signal wire shorted to 12 V
- PossibleChafing or water in harness or connector
- PossibleA connected sensor faulty internally
- RareModule internal voltage regulator or components
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.